E-L9637D

Overview

The E-L9637D is a monolithic integrated circuit providing standard ISO 9141 compatible interface functions for automotive applications. It operates within a power supply voltage range of 4.5 V to 36 V, with transient tolerance up to 40 V and reverse battery protection down to -24 V. The device features a bidirectional K-I/O pin with a typical output current limitation of 60 mA and a wide input/output voltage range from -24 V to VS. Key electrical parameters include a standby mode current consumption of ≤ 1 µA at VCC ≤ 0.5 V and a low quiescent current in the off condition of 120 µA. It is qualified under AEC-Q100 standards and housed in an SOIC-8 package.

Feature Summary

• Provides ISO 9141 compliant half-duplex communication between vehicle onboard microcontrollers and off-board diagnostic systems via the ISO K line.
• Includes overtemperature shut-down functionality that is selectively applied to the K-I/O pin to protect against thermal stress.
• Ensures defined output states during undervoltage conditions or power supply interruptions, enhancing system reliability.

Applications

• Automotive diagnostic interfaces connecting ECUs to external scan tools.
• In-vehicle networking for chassis and safety systems requiring ISO 9141 protocols.
• Body and convenience electronic control units utilizing serial link bus interfaces.

Procurement Notes

Verify the specific ordering suffix and manufacturing date code upon request, as availability may vary by region. Confirm RoHS compliance status and humidity sensitivity handling requirements before storage. Ensure the procurement channel provides valid traceability documentation for automotive-grade components. Cross-reference the manufacturer part number with official STMicroelectronics catalogs to avoid counterfeit risks.

Selection Notes

Select this component when designing systems requiring strict adherence to ISO 9141 specifications for automotive diagnostics. Consider the SOIC-8 package constraints for PCB layout and thermal management. Evaluate the need for AEC-Q100 qualification if the application targets automotive production lines. Compare the low standby current benefits against other interface solutions for power-sensitive designs.

Part Context

The L9637 series serves as a dedicated serial link bus interface within STMicroelectronics' automotive portfolio. It complements other transceivers like the L9613 and L9615 by focusing specifically on ISO 9141 compatibility. This family supports reliable data transmission in harsh electromagnetic environments common in vehicle electronics.

Replacement Considerations

The L9637D is the direct functional equivalent within the same series. Verify pin-to-pin compatibility and electrical parameter alignment before substituting with other ISO 9141 interface ICs from different manufacturers.